Ice Sheets can retreat and grow in ‘geological instant’ so global warming may be ‘irreversible’

The current shrinking of glaciers may be irreversible, as research shows that they can expand in a ‘geologic instant’.

Scientists from the University at Buffalo discovered that a fast-moving glacier on the Greenland Ice Sheet grew rapidly during a period when the Earth was cooling several thousand years ago.

The finding adds to a growing body of evidence indicating that ice sheets can not only shrink in response to abrupt warming, but also reverse course and expand in response to abrupt cooling.

The paper, published on June 21 in Nature Geoscience, describes fieldwork demonstrating that a prehistoric glacier in the Canadian Arctic rapidly retreated in just a few hundred years.

The proof of such rapid retreat of ice sheets provides one of the few explicit confirmations that this phenomenon occurs.

“A lot of glaciers in Antarctica and Greenland are characteristic of the one we studied in the Canadian Arctic,” said Jason Briner, Ph.D., assistant professor of geology in the UB College of Arts and Sciences and lead author on the paper. “Based on our findings, they, too, could retreat in a geologic instant.”